With development of science and technologies, functions of a terminal become increasingly diversified, and therefore an intelligent terminal emerges as the times require. An intelligent terminal refers to a terminal that has an independent mobile operating system and that can extend terminal functions by installing programs such as application software and games. The mobile operating system of the intelligent terminal may be an Android system, an iOS system, a Symbian system, a BlackBerry operating system, a Bada system, a Windows Phone system, a web operating system, or some other embedded Linux systems.
An intelligent terminal is equipped with an original system at delivery. The original system highly matches the terminal. However, due to openness of an open-source mobile operating system of a terminal and rejuvenation and diversification of intelligent terminal users, changing the mobile operating system of the intelligent terminal by means of ROM flashing has become a common behavior.
Currently, a most common ROM flashing manner is to enter a system recovery mode (recovery mode) of a terminal, and when a user selects system recovery or system update according to a prompt, write system software in a ROM flashing package provided by the user into a system partition of a built-in memory in the intelligent terminal, to overwrite an original system. The original system is totally overwritten, and therefore, if the user intends to recover the previous system, ROM flashing needs to be performed again. In addition, a risk exists during a process of performing ROM flashing again, and the recovery mode of the intelligent terminal may even be destroyed. If the recovery mode of the intelligent terminal is destroyed, the intelligent terminal can be repaired only at a repair shop.